public class TestInterface {
    public static void main(String[] args) {
        System.out.println(Inter.NUM);
        InterImpl i = new InterImpl();
        i.method();
    }

}
interface Inter {
    int NUM = 10;

    void show();
}
class InterImpl implements Inter{

    public void method(){
        int NUM = 20;
        System.out.println(NUM);
    }

    public void show(){

    }
}